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The Convective Instability of BEK Family of Non-Newtonian Rotating Boundary-Layer Flows
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The BEK family of flows have many important practical applications such as centrifugal pumps, steam turbines, turbo-machinery and rotor-stator devices. The Bödewadt, Ekman and von Kármán flows are particular cases within this family. The convective instability of the BEK family of rotating boundary-layer flows has been considered for generalised Newtonian fluids, power-law and Carreau fluids. A linear stability analysis is conducted using a Chebyshev collocation method in order to investigate the effect of shear-thinning and shear-thickening fluids for generalised Newtonian fluids on the convective Type I (inviscid crossflow) and Type II (viscous streamline curvature) modes of instability. The results reveal that shear-thinning power-law fluids have a universal stabilising effect across the entire BEK family of flows. However, the convective instability characteristics for the shear-thinning and shear-thickening Carreau fluids are affected by the value of the relaxation parameter k. The results reveal that Shear-thinning Carreau fluids have a small destabilising effect, while shear -thickening fluids have a slight stabilising effect on the Type I and Type II mode for the BEK family of flows when k =100. On the other hand, shear-thinning and shear-thickening Carreau fluids are found to have stabilising and destabilising effect, respectively for optimal relaxation value ko. The results are presented in terms of neutral curves and growth rates. Furthermore, an energy analysis is presented to gain insight into the underlying physical mechanisms behind the stabilising effects of generalized Newtonian fluids. In conclusion, the use of shear-thinning power-law and Carreau fluids with optimal value ko can be recommended to reduce skin-friction drag in enclosed rotor-stator devices for the entire BEK family of flows.

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Publication Date
Sun Dec 16 2018
Journal Name
Al-academy
Reflection of political variables in the design of the Journal cover
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the political changeable is important reflection in areas of life and the designers tried to high light it in the cover of Journal promised time Journal a fertile square to show reflection of political changeable, and triad  to  search  the  current  path. The  first  chapter organized according to axes, problem of  research formulated according to question:- what are reflections of political changeable in magazine cover?

    The importance of research depth of specialized approach on level of technical and stylistic as ago al ago as in: the baring of political changeable in design of journal's cover. The research moves in cognitive border from 2013 to 2017 and selection of t

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Publication Date
Mon Mar 07 2022
Journal Name
Journal Of Educational And Psychological Researches
Educational Implications of the Concept of Desertion in the Holy Quran
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The purpose of the present study is to identify the comprehensive concept of desertion through the Holy Qur’an and to derive some educational implications related to the concept of desertion and its editing. The also aims to explain the images and forms of desertion. The researcher used the qualitative analytical method. The study concluded that the comprehensive concept of desertion was represented in moving from the country of polytheism to the country of Islam, singularity, alienation, and isolation, leaving, repelling and showing off, abandoning the wife in bed, and reciting from the Qur’an recitation, action, and arbitration, insulting, abandoning, delirium, intersection, and manipulation. The researcher has drawn many education

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Publication Date
Wed May 17 2023
Journal Name
College Of Islamic Sciences
The origins of the structure of nominative pronouns, a linguistic study
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The Arabic pronouns received a lot of attention from the ancient Arab grammarians, so they explained their origins, the different forms of their structure, and the aspects of the Arabs’ use of them, and explained the aspects and reasons for these uses, with what they had of linguistic insight, which guided them to clarify the truth of these pronouns.
And recently, this research seeks new knowledge of the development of the structure of the nominative pronouns (he), (she), (them), (taa), and (waw) between dialects and towards classical Arabic, by analyzing the structure of these pronouns into their components. Its linguistic formulas are traced from the ancient Arabic texts, and by ancient I mean the texts of the era of linguistic ci

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Publication Date
Tue Dec 28 2021
Journal Name
College Of Islamic Sciences
The concept of the phenomenon of nuns: an analytical ideological study
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ملخص البحث باللغة الإنجليزية

The concept of the phenomenon of nuns: an analytical ideological study

Dr. Samia bint Yassin Al-Badri

Department of Islamic Doctrine & Contemporary Ideologies

College of Shariʿah & Islamic Studies

Qassim University

 

The study of concepts is one of the main pillars of doctrinal studies, in order to understand the formation of the concept, and to understand its contexts in religious sources, in order to be systematically criticized; So, this research came with the title:

The concept of the phenomenon of nuns, an analytical doctrinal study

The study concluded with resu

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Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
The Effect of Additives on The Performance of Hydrostatic Thrust Bearings
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The paper is concerned with, the behavior of the hydrostatic thrust bearings lubricated with liquid-solid lubricants using Einstein viscosity formula, and taking into account the centrifugal force resulting from high speed.  Also studied is the effect of the bearing dimensions on the pressure, flow rate, load capacity, shear stress, power consumption and stiffness.

The theoretical results show an increase in load capacity by (8.3%) in the presence of solid graphite particles with concentration of (16%) by weight as compared with pure oil, with increasing shear stress.  .

In general the performance of hydrostatic thrust bearings improve for load carrying capacity, volume flow rate,

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Publication Date
Sun Jun 04 2017
Journal Name
Baghdad Science Journal
Improvement of the technique for the solution method of Gauss Seidel
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In this paper, a new approach was suggested to the method of Gauss Seidel through the controlling of equations installation before the beginning of the method in the traditional way. New structure of equations occur after the diagnosis of the variable that causes the fluctuation and the slow extract of the results, then eradicating this variable. This procedure leads to a higher accuracy and less number of steps than the old method. By using the this proposed method, there will be a possibility of solving many of divergent values equations which cannot be solved by the old style.

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Publication Date
Sat Aug 16 2025
Journal Name
Hammurabi Journal For Studies
(The impact of legislative drafting on the achievement of electoral justice)
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Publication Date
Sat Jun 01 2013
Journal Name
Int. J. Nanoelectronics And Materials
The response of a window glass to the frequencies of sound
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Publication Date
Mon Dec 31 2012
Journal Name
Al-khwarizmi Engineering Journal
The Effect of Doppler Phenomenon on the Speed of Blood Flow
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This research studying the phenomenon of Doppler (frequency Doppler) as a method through which the direction and speed of the blood cells flows in blood vessels wear measured. This Doppler frequency is relied upon in medicine for measuring the speed of blood flow, because the blood flow is an important concept from the concepts of medicine. It represents the function and efficient of the heart and blood vessels in the body so any defect in this function will appear as a change in the speed of blood flow from the normal value assumed. As this speed changes alot in cases of  disease and morbidity  of the heart, so in order to identify the effect of changing the Doppler frequency on the speed of blood flow and the relationship of

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Publication Date
Sat Jan 12 2019
Journal Name
Journal Of The College Of Education For Women
The geomorphological associated of Sebkha in the Mesopotamia- plain of Iraq
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The Sebkha of geomorphological aspects of evaporative where climate leads active role, which forms part of the earth's surface in the form of Iraqi Mesopotamia plain who of the most fertile land, and because of natural factors and human Common turned most of the arable land to the territory of Sebkha. It was to determine the exact geomorphological associated of Sebkha formats by field work such as: Alnbaka, lakes, salt flats, and other forms of Small is: bridges salt, mud cracks, salt ponds, Rectangles and polygons salt, Sahaf salt, salt domes, salt gravel, bumps saline (salt points), Ash salt, salt bows, in detail and accurately documented Terrestrial Photogrammetry field and were compared to the levels and standards varieties have been

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